Self-propelled floor cleaning apparatus with movable brush

ABSTRACT

A floor cleanning apparatus includes a frame supported for rolling movement on a floor or other surface by a pair of drive wheels and a follower wheel. The frame carries an internal combustion engine driving a vacuum pump and a hydraulic pump. A pair of rotating brushes are mounted forwardly of the frame. A first one of the brushes is fixed to the forward portion of the frame in a manner which prevents lateral movement of the brush relative to the machine. The second one of the brushes is connected to the first brush for pivotal swinging movement from a first position sidewardly of the first brush to a second position forwardly of the first brush. A hydraulic cylinder, mounted on the first brush and operatively coupled to the second brush, provides power to move the second brush between the first and second positions. The drive wheels and each of the brushes are rotated by hydraulic motors in turn driven by hydraulic fluid supplied from the hydraulic pump. The frame carries a vacuum holding tank to which the vacuum pump is connected. The inlet to the vacuum tank is positioned adjacent the rear of the frame and forwardly of a V-shaped wiper blade, also attached to the rear portion of the frame. The V-shaped wiper blade contacts a surface to be cleaned and directs cleaning fluid and dirt present on the floor toward the vacuum inlet. A second wiper blade is mounted on the second brush to direct cleaning fluid from the second brush toward the V-shaped wiper blade. The frame also carries a cleaning fluid holding tank from which cleaning fluid can be dispensed to the brushes.

United States Patent [191 OConnor et al.

[ 1 Feb. 18,1975

1 1 SELF-PROPELLED FLOOR CLEANING APPARATUS WITH MOVABLE BRUSH [75] Inventors: James M. OConnor, Seattle;

Raymond A. Nelson, Portland; Gary Pjiee srab l evkee. a l. of a [73] Assignees: James M. OConnor; Donald M.

Goodfellow, both of Edmonds, Wash.

[22] Filed: Mar. 24, 1972 [21} Appl. No: 237,846

[52] US. Cl 15/50 R, 15/87, 15/320 [51] Int. Cl A471 11/00 [58] Field of Search 15/49 R, 50 R, 83, 87, 15/320; 192/46 [56] References Cited UNITED STATES PATENTS 3,197,798 8/1965 Brown et al. 15/87 X 3,241,170 3/1966 Osborn 15/87 3,277,511 10/1966 Little et al. 15/340 X 3,345,671 10/1967 Wilson et al...... 15/50 R X 3,701,177 10/1972 Meyer et al 15/50 R Primary Examiner-Harvey C. Hornsby Assistant Examiner-C. K. Moore Attorney, Agent, or FirmChristensen, OConnor, Garrison & Havelka [57] ABSTRACT A floor cleanning apparatus includes a frame supported for rolling movement on a floor or other surface by a pair of drive wheels and a follower wheel. The frame carries an internal combustion engine driving a vacuum pump and a hydraulic pump. A pair of rotating brushes are mounted forwardly of the frame. A first one of the brushes is fixed to the forward portion of the frame in a manner which prevents lateral movement of the brush relative to the machine. The second one of the brushes is connected to the first brush for pivotal swinging movement from a first position sidewardly of the first brush to a second position forwardly of the first brush. A hydraulic cylinder, mounted on the first brush and operatively coupled to the second brush, provides power to move the second brush between the first and second positions. The drive wheels and each of the brushes are rotated by hydraulic motors in turn driven by hydraulic fluid supplied from the hydraulic pump. The frame carries a vacuum holding tank to which the vacuum pump is connected. The inlet to the vacuum tank is positioned adjacent the rear of the frame and forwardly of a V- shaped wiper blade, also attached to the rear portion of the frame. The Vshaped wiper blade contacts a surface to be cleaned and directs cleaning fluid and dirt present on the floor toward the vacuum inlet. A second wiper blade is mounted on the second brush to direct cleaning fluid from the second brush toward the V-shaped wiper blade. The frame also carries a cleaning fluid holding tank from which cleaning fluid can be dispensed to the brushes.

12 Claims, 9 Drawing Figures PATENTED FEB] 8 1975 SHEET 2 BF 4 PATENTEU m1 81975 SHEET 3 OF 4 E @9 xot mm SELF-PROPELLED FLOOR CLEANING APPARATUS WITH MOVABLE BRUSH BACKGROUND OF THE INVENTION The present invention relates to floor cleaning apparatus and more particularly to a self-propelled cleaning machine with rotating brushes, at least one of which is mounted for lateral movement.

Prior art cleaning machines of the general type to which the present invention relates are known in the art. One problem with the prior art machines arises when they are used in display areas, such as supermarkets. Generally shopping aisles are formed in superman kets by permanently located display shelves. Typically, temporary displays are located in the aisles forming obstacles which partially block the aisles. With prior art cleaning machines when such temporary display is encountered, the machine operator is required to direct the machine toward the side of the display, back up the machine, clear around the display, turn the machine around and then clean on the opposite side of the display. This operation, of course, is time consuming and detrimental to the overall efficiency necessary to clean supermarket floors economically. Many times the operator of a cleaning machine will not attempt to clean around such temporary displays with a machine, but return to clean these areas by hand.

Furthermore, the machines of the prior art have not generally been designed to operate efficiently and economically For example, prior art machines have been propelled by gasoline internal combustion engines driving wheels through a gear or belt train. Complex machanical drive trains have been utilized to drive the rotating brushes. Some machines have used electric motors which required rather long extension power cords or storage batteries. Such machines have been cumbersome and subject to many mechanical difficulties.

it is an object of the present invention to provide a movable cleaning head on a self-propelled machine to facilitate quick and efficient cleaning of corner areas around boxes or merchandise stacked on a floor. It is a further object of the present invention to eliminate a part of the man hours previously required to clean such areas. It is a further object of the present invention to reduce and eliminate many of the mechanical power transmission problems inherent in the prior art machines. It is a further object of the present invention to eliminate long extension cords and the storage batteries required for electrically powered cleaning machines. It is a further object of the present invention to provide a power transmission system which can rotate the brushes, drive the wheels and power auxiliary equipment. It is a further object of the present invention to provide a low cost, self-propelled cleaning machine with the foregoing attributes which further provide relatively troublefree operation.

It is a further object of the present invention to provide a self-propelled cleaning machine which combines all equipment necessary for a cleaning operation, for example, cleaning fluid supply, scrubbing, selfpropulsion, floor wiping, and cleaning fluid removal. It is a further object of the present invention to provide an apparatus which is flexible and can be easily adapted to a variety of cleaning tasks. It is a further object of the present invention to provide interchangeable cleaning fluid and vacuum holding tanks. It is a further object of the present invention to provide two rotating scrub brush members, one of which is attached for lateral movement with respect to the operational path of the machine. It is a further object of the invention to provide a third auxiliary brush which increases the width of the path being scrubbed.

It is a further object of the present invention to provide a machine which will not overly tax its operator and which furthermore provides easy control of the machine functions from the operating station.

SUMMARY OF THE INVENTION The foregoing and other objects which will become apparent from reading the following specification are provided in a machine for contacting a surface with a rotary fluid working tool which includes a'frame supported by wheels and having a forward and rearward end. The machine includes first and second rotary tool means such as rotary scrub brushes. The first rotary tool means is adapted to contact. the surface and includes a first sub-frame which is mounted on the forward end of the frame. The second rotary tool means is also adapted to contact the surface and is located adjacent the forward end of the frame and the first tool means. The second tool means also has a sub-frame which is mounted by mounting means on the first subframe for movement between a first position located sidewardly of the first tool means and a second position located substantially forwardly of the first tool means. A prime mover, which can be self-contained, is mounted on the frame. Transmission means is provided for operatively connecting the prime mover means to drive the rotary tool means. One aspect of the present invention provides means for detachably mounting the second tool means to the first too] means.

BRIEF DESCRIPTION OF THE DRAWINGS A better understanding of the present invention can be derived by reading the ensuing specification in conjunction with the accompanying drawings wherein:

FIG. 1 is an isometric view of the floor cleaning machine of the present invention;

FIGS. 2 and 3 illustrate different configurations of the machine of FIG. 1;

FIG. 4 is a plan view of the machine of the present invention showing some components thereof in dotted outline;

FIG. 5 is an elevation view partially broken away, of the machine of the present invention showing some components thereof in dotted outline;

FIG. 6 is an elevation view of the forward portion of the machine of the present invention showing the forwardly positioned rotary brush in an elevated position;

FIG. 7 is a detailed view of the pivot block connecting the laterally movable brush to the fixed brush;

FIG. 8 is a plan view of a modified form of the machine shown in FIG. 4; and

FIG. 9 is a schematic diagram of the hydraulic system of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1, the floor cleaning machine, generally designated 10, includes a base member 12, an upright frame member 14 attached to the rear of the base member 12, and a cabinet 16 enclosing the forward portion of the machine 10. An interchangeable cleaning fluid and vacuum holding tank 18 is removably mounted on base member 12. It is held to the cabinet 16 and frame member 14 by latches 20.

A first brush assembly 22 is mounted adjacent the forward portion of the machine by suitable linkagev 24. The linkage 24 is designed to prevent lateral movement of the brush with respect to the machine 10. The brush assembly 22 can be moved upwardly by means of cable 152 to raise it above the surface being cleaned. The linkage 24 is designed to pivot and support the brush assembly 22 in its upward or raised position. A second brush assembly 26 is mounted adjacent the brush assembly 22. In a preferred form of the invention the brush assembly 26 is mounted on brush assembly 22 by means of two links 28. Each of the links are pivotally attached to brush assembly 26 at one end and are pivotally attached to pivot block 30 at the other end. Pivot block 30 will be discussed in detail later. Brush assembly 26 can be moved from the position shown to a position longitudinally adjacent the forward end of the brush assembly 22. The lateral movement occurs through the pivot block 30, which is pivoted on the brush assembly 22 by hydraulic piston and cylinder assembly 32. Hydraulic motors 34 and 36 respectively form part of brush assemblies 22 and 26. Motors 34 and 36 are connected in series to a hydraulic fluid source (not shown) by hydraulic lines 38, 40 and 42.

An internal combustion engine 44 is mounted on the forward portion of the base member 12. A belt 46 running on pulleys 48 and 50 drives a vacuum pump 52 mounted on bracket 54 which is in turn connected to a forward upright frame member 55. The engine 44 also drives a hydraulic pump as described later.

The machine 10 is supported by drive wheels 56 and a follower wheel 58 attached to the bottom of base member 12. The drive wheels 56 are operatively driven by a hydraulic motor (not shown). The follower wheel 58 is of the caster type and is mounted for pivotal movement to the bottom of base 12. The machine is guided along a cleaning path by the operator who grasps the handles 60 mounted on the rear frame member 14.

The cleaning fluid/holding tank 18 is removably mounted on the base 12 of the machine 10. As shown in FIG. 2 the tank 18 has been removed from the machine. Also in FIG. 2 the second brush assembly 26 is shown in its longitudinal position forward of the brush assembly 22. In FIG. 3 a larger cleaning fluid/holding tank 62 is shown mounted on the machine 10. Also in FIG. 3 a third fixed brush assembly 64 is attached to brush assembly 22. The third brush assembly 64 increases the width of the path which the machine can clean in a single traverse.

Referring now in detail to the plan and elevation views of FIGS. 4 and 5, the machine 10 is illustrated with some of its components shown in dotted outline. The drive wheels 56 are mounted on each side of the machine 10 near the forward end. The single follower wheel 58 is located near the center of the base 12 toward the rearward end of the machine 10.

A wiper blade assembly 70 is mounted on base 12 rearwardly of the follower wheel 58. The blade assembly 70 extends laterally beyond the widest portion of the first brush assembly 22. Spent cleaning fluid will be wiped from the cleaned surface by the blade 80, which forms part ofthe blade assembly as the machine 10 traverses a scrubbing path in a forward direction. The wiper blade assembly 70 is mounted for vertical movement by linkage 74. Blade assembly 70 is held in a downwardly position by serrated arm 76 which engages the upper frame member 78 of the blade assembly 70. Serrated arm 76 is pivotally attached to the bottom of bottom of base 12. As best seen in FIG. 5, a rubber blade 80 is positioned in a suitable receiver in frame member 78. The blade assembly 70 is biased in an upper direction by means of a coil spring 82 connected to a foot pedal 84, which in turn is connected to the blade assembly 70. A second coil spring 86 is also connected to a foot pedal 88 in turn connected to serrated arm 76. To raise the blade assembly 70, a force is applied to foot pedal 58disengaging serrated arm 76 from frame member 78. Coil spring 82 then raises assembly 70. Tolower the assembly 70, force is applied to pedal 84. The outer ends of the blade are positioned further forwardly relative to the base 12 than is the center portion of the blade, so that the blades converge inwardly and rearwardly to a central location 90.

Tank 18 is a combined cleaning fluid reservoir 92 and a vacuum holding tank 94. The cleaning fluid reservoir 92 constitutes the upper portion of the tank 18, while the lower portion of the tank, 18 comprises the vacuum holding tank 94. The open end of a vacuum inlet conduit 96 is positioned adjacent to and forwardly of the central location of the blade 80 to draw used cleaning fluid and dirt directed toward the location 90 by the blade 80 into vacuum holding tank 94. The inlet conduit 96 runs upwardly through the bottom of the holding tank 94 and terminates at its other end near the top of the holding tank 94. A baffle 98 is provided on the roof of tank 94 to prevent spent cleaning fluid discharged from conduit 96 from entering conduit 100 which leads to the vacuum pump 52. To drain the holding tank 94, hose connected to the bottom of tank 94 is lowered, thus allowing accumulated cleaning fluid to gravitate from the tank.

Water or other suitable cleaning fluid from reservoir 92 is drained by gravity through outlet port 102 into a valve 104. From valve 104 the water proceeds along conduit 106 (partially broken away) to each of the brush assemblies 22 and and 26. The flow of water through valve 104 is controlled by lever 108 connected to the valve 104 by suitable linkage (not shown).

The internal combustion engine 44 is connected via a toothed belt 112 to the drive shaft of a hydraulic pump 114. The hydraulic pump 114 is located in a hydraulic fluid reservoir or sump 116 mounted under the base 12 of the machine 10. Hydraulic fluid lines 38 are connected to the outlet of the hydraulic pump 114 while fluid line 42 is in fluid communication with the reservoir 116.

Hydraulic motor is mounted under the base 12 of the machine. The hydraulic motor 160 is drivingly connected to axle 162 through chain and sprocket arrangement 172 (shown schematically in FIG. 4) on which drive wheels 56 are rotatably mounted. A disc 164 is affixed to the ends of the axle 162. Arms 166, extending radially outwardly from pivotal mountings on the sides of discs 164, are biased by spring in the direction shown against a stop in the form of a pin 174 extending outwardly from disc 164. Pins 168 extend radially inwardly along the sides of wheels 56. Pins 168 and arms 166 cooperate to provide a simple differential mechanism for the wheels 56. Thus, as the axle 162 is rotated in a counterclockwise direction, the arm 168 will ride against pin 174 and will contact the front side of the pin 166 extending radially inwardly from the periphery of the wheel, thereby driving the wheel 56 in a forward, counterclockwise direction. The differential allows the axle to rotate within the wheel when the axle is reversed and driven in a clockwise direction. Even though the axle free-wheels when reversed, the presenec of bearing friction between the axle and the wheel will assist the operator when he pulls backwardly on the machine to manually reverse its direction.

The brush assemblies 22 and 26 include hollow cylindrical frame members 118 and 120. Circular brushes 122 and 124 are mounted for rotation in suitable bearings on the frame members 118 and 120. The drive shaft of the hydraulic motors 34 and 36 are coupled to and rotate brush members 122 and 124. Linkage 24, connecting the brush assembly 22 to the base 12 of the machine 10, includes link member 128 pivotally attached at 130 to a second link 132. Link 132 is fixed to flange 134 on the frame member 118 at its other end. Link 128 is pivotally attached by bar 136 to the bottom of base 12. A disc 140 is attached to the link 128 and rotates with the link 128. A notch is disc 140 mates with a pin 142 on bar 144 when the brush assembly 22 is in its lower position. To raise the brush assembly 22, bar 144 is first raised to disengage pin 142, as shown in FIG. 6. Bar 146, pivotally mounted to forward frame member 55 and attached to arm 150, is then moved in the direction of the arrow 148. Movement of bar 146 will raise arm 150 to pull cable 152 inan upwardly direction. Cable 152 is attached to the brush assembly frame 118. A pawl and ratchet 153 are provided on bar 146 to hold the brush assembly in its up ward position.

As best seen in FIG. 4, a second wiper blade assembly 76 is mounted by arms 178 on the frame 120 of second brush assembly 26. The blade assembly 176 is of similar construction to blade assembly 70 and includes a rubber blade 180 fitted into a suitable receiver. Links 178 are pivotally connected at each end respectively to the frame 120 and the blade assembly 176. When the brush assembly 26 is in its laterally displaced position, the rubber blade 180 will direct spent cleaning fluid and dirt from brush assembly 26 sidewardly to be picked up by the blade assembly 70.

A roller 182 is mounted for rotation about a vertical axis at the inboard end of assembly 76. Roller 182 rides against the periphery of first brush frame 118. As the second brush assembly 26 is moved laterally to a position forward of brush assembly 22, the wiper blade 76 will follow to the position shown in dotted outline. In this position the blade 180 will still direct spent cleaning fluid rearwardly from the brush assembly 26 to be picked up by the blade assembly 70.

Referring now to FIG. 7 the details of the pivot block 30 are shown. It includes a base plate 184 which is mounted for pivotal movement on a pin 186 mounted on the frame 118 of brush assembly 22. Pin 186 mates with hole 188 in plate 184. The base plate 184 is connected by a pin to yoke 194 of the piston arm 192 of the hydraulic cylinder assembly 32 (shown in previous FlGS.). Two upstanding pins 196 mate with holes 198 in a second plate 200. Linkage arms 28, connected at one end to brush assembly 26, are pivotally connected via pins 202 to a flange 204 on plate 200. The outboard brush assembly 26 is easily removable from the main machine by first disconnecting quick-connect hydraulic couplings from the hydraulic motor 36 and by liftingv the second plate 200 to disengage it from the pins 196. This feature of the present invention is especially helpful when transporting the machine from one job or location to the next. The outboard brush assembly can be stacked on the fixed brush assembly, thus reducing the space required for transportation.

Referring now to FIG. 8 a second embodiment of the invention is shown. This embodiment of the invention includes a third brush assembly 210 similar in construction to brush assembly 26. A third hydraulic motor 212 is provided and interconnected by conduits 214 in se- 'ries with the other brush motors. Two arms 216 consimilar to that described in conjunction with FIG. 6

could be used ifdesired. In addition, a second hydraulic cylinder assembly can be utilized to laterally swing the brush assembly 210 to a position forward of the machine 10. A third wiper blade 218 is also connected to the brush assembly 210 to direct spent cleaning fluid from the brush assembly 210 rearwardly toward the main blade assembly (shown in previous FIGS.) Since a greater path can be cleaned at one time with this embodiment, it is most advantageous to use the larger cleaning fluid and vacuum holding tank 62, shown in FIG. 3.

FIG. 9 is a schematic diagram of a preferred form of the hydraulic system to be utilized with the present invention. The hydraulic fluid sump 116 of the present invention is schematically shown. A hydraulic pump 114 is driven by means of an internal combustion engine 44. Hydraulic pump 114 draws fluid from the sump 116 and forwards it along conduit 226. Conduit 226 enters one port of a four way valve 228. The four way valve 228 is shown in its b position neutralizing all systems downstream of the four way valve 228. A return conduit 230 is provided to return fluid to the sump 116. Thus fluid enters the valve 228 via conduit 226 and returns to the sump via conduit 230.

When valve 228 is in position a, hydraulic fluid is forwarded through valve 228 along conduit 38. Conduit 38 is connected in series with first and second brush motors 34 and 36. The hydraulic motors 34 and 36 are connected to rotate brushes 122 and 124. The fluid outlet of brush motor 36 connects to conduit 42 which in turn connect to a check valve 244. Check valve 244 is positioned to allow flow in the direction away from hydraulic motor 36. The fluid outlet of check valve 244 is connected to conduit 246 which in turn is connected to the inlet port of a variable valve 248. Variable valve 248 is designed to proportion flow between first outlet conduit 250 and second outlet conduit 252. Conduit 252 is connected between variable valx 8 anir 1 428221.

When four way valve 228 is in position a and variable valve 248 directs fluid into conduit 252, brush motors 34 and 36 are run at a constant speed in a forward direction. Check valve 224 prevents reverse motion ofbrush motors 34 and 36 when the four way valve 228 is moved to its 0 position Outlet conduit 250 from variable valve 248 is connected to an inlet port of a second four way valve 254. In position b" as shown fluid is returned to the sump by a conduit 256. The conduit 256 has interposed therein an air/hydraulic fluid heat exchanger 258 and a filter 260. When the four way valve 254 is moved to position the hydraulic fluid flows into conduit 262 and through wheel drive motor 160. The fluid outlet from wheel drive motor 160 is connected to conduit 266 which returns to the four way valve 254. In position c the fluid then returns to sump 116 via conduit 266. When the four way valve 254 is moved to position a, the flow through wheel drive motor 160 is reversed, reversing the rotational direction of the axle to provide assistance in reversing the direction of the machine as explained above. When the four way valve 254 is in position c the variable valve 248 may be utilized to vary the forward speed of the machine.

When the four way valve 228 is in position 0 and the four way valve 254 is in position c, hydraulic fluid exits from four way valve 228 into conduit 268 through check valve 270 and into the conduit 246 connected to the entrance port to variable valve 248. in this position the brush motors 34 and 36 are inactivated, due to the presence of check valve 244. However, the forward motion of the machine continues via motor 160.

A braking system is also interconnected with the wheel drive motor circuit for operation when the valve 254 is in the a position and valve 248 is in an of position, whereby all flow through the valve 248 is diverted through conduit 252. The braking system is operative only when the machine is backed down an incline as when backing the machine down a ramp from a truck to the ground. The braking system includes a conduit 272 connected to one side of the motor 160. The other end of conduit 272 is connected to check valve 274 which is adapted to allow flow from the sump 220 through conduit 276 toward the motor 160. Thus when the four way valve 254 is in position, a hydraulic fluid is drawn from the sump 116 by the motor 160, now acting as a pump, and returns to the sump 116 via conduit 256. Thus a braking action is effected.

Conduit 226 is also connected to conduit 278 which is in turn connected to a third four way valve 280. In position b no flow is allowed through the valve 280. When valve 280 is moved to position a, flow occurs into conduit 282 connected to one end of cylinder 284 of the assembly 32. The piston arm 286 of the assembly 284 is operatively connected to the laterally movable brush assembly. Thus, piston 286 is caused to move in a first direction. When the four way valve 280 is moved to position c," flow of hydraulic fluid through valve 280 is reversed so that hydraulic fluid will flow into conduit 288 connected to the other side of the cylinder 284. Thus, the piston arm 286 will be caused to move in the opposite direction. A sump return conduit 290 connects between the four way valve 280 and the sump 116.

The foregoing invention has been described in relation to a preferred embodiment and several alternatives thereto. It will be apparent that various substitutions, alterations, changes and other modifications can be made to the disclosed machine by those of ordinary skill in the art. It is intended that the original concept of the invention be limited only by the definition contained in the appended claims.

What is claimed is:

l. A machine for cleaning a surface comprising:

a frame supported by wheels and having a forward end and a rearward end, said wheels including a pair of spaced drive wheels interconnected by a rigid axle, said axle mounted for rotation in said frame, said wheels mounted for rotation on said axle,

differential drive means associated with said axle and each of said drive wheels, said differential drive means being adapted to drive each said drive wheel in a first direction responsive to rotation of said axle in said first direction and being adapted to allow said axle to rotate in said wheel when said axle is rotated in the opposite direction from said first direction,

a self-contained prime mover mounted on said frame,

a first rotary brush means having a first sub-frame mounted on the forward end of said frame, said first brush means being adapted to contact said surface,

a second rotary brush means having a second subframe located adjacent to the forward end of said frame and adjacent to said first brush means, said second brush means being adapted to contact said surface,

means mounting said second sub-frame on said first sub-frame for movement between a first position located sidewardly of said first brush means and a second position located substantially forwardly of said first brush means, whereby as said machine travels forwardly said first brush means contacts said surface along a path substantially the same as said second brush means when said second brush means is in said second position, and

transmission means operatively coupling said prime mover to drive said first and second rotary brush means and operatively coupling said prime mover to drive said axle.

2. A machine for cleaning a surface comprising:

a frame having a forward end and rearward end, said frame being supported by wheels including drive wheel means for moving said machine along said surface,

a self-contained prime mover mounted on said frame,

a first sub-frame mounted on the forward end of said frame, and a first rotary brush mounted for rotation on said first sub-frame and adapted to contact said surface,

a second sub-frame located adjacent to the forward end of said frame and adjacent to said first subframe, a second rotary brush mounted for rotation on said second sub-frame and adapted to contact said surface, and means mounting said second subframe for swinging movement from a location sidewardly of said first sub-frame to a location forwardly of said first sub-frame,

power transmission means operatively connecting said prime mover to drive said first and second rotary brushes and to drive said drive wheel means, said transmission means including a hydraulic pump having an outlet and an inlet, said hydraulic pump being driven by said prime mover, first and second hydraulic motors operatively connected to drive said first and second brushes, respectively, and a third hydraulic motor operatively connected to drive said drive wheel means, said first, second and third hydraulic motors each having an inlet and an outlet, said inlets being operatively coupled to the outlet of said hydraulic pump to receive hydraulic fluid therefrom, said first hydraulic motor mounted on said first sub-frame and having a drive shaft, said drive shaft being drivably connected to said first rotary brush, said second hydraulic motor mounted on said second sub-frame and having a drive shaft, said drive shaft being drivably connected to said second rotary brush, and

a hydraulic piston and cylinder, and means operatively connecting one of the piston and cylinder to said second sub-frame and means affixing the other of said piston and cylinder to said first sub-frame, said hydraulic piston and cylinder being operatively coupled to the outlet of said hydraulic pump to swing said second sub-frame about its mounting to said first sub-frame.

3. The machine of claim 2 wherein said transmission means includes a hydraulic fluid system comprising:

a hydraulic fluid sump,

first conduit means in fluid communication with said sump and the inlet to said hydraulic pump,

second conduit means placing said first and second hydraulic motors in serial fluid communication with the outlet of said hydraulic pump,

a first check valve means, and third conduit means in fluid communication between said first check valve means and the outlet of said second hydraulic motor, said first check valve means operative to allow flow away from said first and second hydraulic motors,

fourth conduit means in fluid communication between said third conduit means and the inlet to said third hydraulic motor,

fifth conduit means in fluid communication between the outlet of said third hydraulic motor and said sump,

sixth conduit means is fluid communication between said fourth conduit means and said sump, and

a first four-way valve means operatively interposed in said second and sixth conduit means.

4. The machine of claim 3 wherein said hydraulic fluid system further comprises;

second check valve means interposed in said sixth conduit means between said first four-way valve means and said fourth conduit means, said second check valve means operative to allow flow in a direction from said first four-way valve means to said fourth conduit means,

seventh conduit means in fluid communication with said sump, and

variable flow valve means interposed in said fourth conduit means and operatively coupled to said seventh conduit means to proportion hydraulic fluid flow between said fourth conduit means and said seventh conduit means.

5. The machine of claim 4 wherein said hydraulic fluid system further comprises:

a second four-way valve means operatively interposed in said fourth and fifth conduit means, said second four-way valve means located in said fourth conduit means between said variable flow valve means and said third hydraulic motor.

6. The machine of claim 5 wherein said hydraulic cylinder has inlets for supplying fluid thereto for reciprocatively actuating said piston, said hydraulic fluid system further comprising:

eighth conduit means in operative fluid communication between said second conduit means and a first inlet of said hydraulic cylinder,

ninth conduit means in operative fluid communication between a second inlet of said hydraulic cylinder and said sump, and

third four-way valve means operatively interposed in said eighth and ninth conduit: means.

7. The machine of claim 5 wherein said hydraulic fluid system further comprises:

fluid working tool comprising:

a frame supported by wheels and having a forward end and a rearward end,

a prime mover mounted on said frame,

a first rotary tool means including a first sub-frame mounted on the forward end of said frame. and including a first tool rotatably mounted on said first sub-frame, said first tool means being so constructed to contact said surface with said first tool,

a second rotary tool means located adjacent to the forward end of said frame and adjacent to said first too] means, said second tool means including a second sub-frame and including a second rotary tool rotatably mounted on said second sub-frame, said second tool means being so constructed to contact said surface with said second "tool,

mounting means mounting said second sub-frame on said first sub-frame for movement in a vertical direction relative to said first sub-frame when said first and second tools are in contact with said surface, and

power transmission means operatively coupling said prime mover to drive said first and second rotary tool means.

9. A machine for contacting a surface with a rotary fluid working tool comprising:

a frame supported by wheels and having a forward end and a rearward end,

a prime mover mounted on said frame,

first rotary tool means including a first sub-frame mounted on the forward end of said frame, and including a first tool rotatably mounted on said first sub-frame, said first tool means being so constructed to contact said surface with said first tool,

a second rotary tool means located adjacent to the forward end of said frame and adjacent to said first tool means, said second tool means including a sec ond sub-frame and including a second rotary tool rotatably mounted on said second sub-frame, said second tool means being so constructed to contact said surface with said second tool,

mounting means mounting said second sub-frame on said first sub-frame for movement between a first position located sidewardly of said first tool means and a second position located substantially forwardly of said first tool means, said second tool means in said second position being located so that, as said machine travels in a forward direction, said first tool contacts said surface along substantially the same path as said second tool contacts said sur' face,

power means connected between said first sub-frame and said second sub-frame for moving said second tool means between said first and second positions, and

power transmission means operatively coupling said prime mover to drive said first and second rotary tool means.

10. The machine of claim 9 wherein said power means comprises:

fluid working tool comprising:

a frame supported by wheels and having a forward end and a rearward end,

a prime mover mounted on said frame,

a first rotary tool means including a first sub-frame mounted on the forward end of said frame, and including a first tool rotatably mounted on said first sub-frame, said first tool means being so constructed to contact said surface with said first tool,

a second rotary tool means located adjacent to the forward end of said frame and adjacent to said first tool means, said second tool means including a second sub-frame and including a second rotary tool rotatably mounted in said second sub-frame, said second tool means being so constructed to contact said surface with said second tool,

mounting means detachably mounting said second sub-frame to said first sub-frame for movement between a first position located sidewardly of said first tool means and a second position located substantially forwardly of said first tool means, and

power transmission means operably coupling said prime mover to drive said first and second rotary tool means.

12. A machine for cleaning a surface comprising:

a frame supported by wheels and having a forward end and a rearward end,

a self-contained prime mover mounted on said frame,

a first rotary brush means having a first sub-frame mounted on the forward end of said frame, said first brush means adapted to contact said surface,

a second rotary brush means having a second subframe and being adapted to contact said surface, said second brush means being located adjacent to the forward end of said frame and adjacent to said first brush means,

means mounting said second sub-frame on said first sub-frame for swinging movement between a first position located sidewardly of said first brush means and a second position located substantially forwardly of said first brush means,

first wiper blade means mounted adjacent the rearward end of said frame to direct fluid to a means for removing said fluid from said surface,

second wiper blade means mounted on and rearwardly of said second brush means, said second wiper blade means adapted to direct fluid present on said floor rearwardly and sidewardly to be picked up by said first wiper blade means as said machine traverses a forward path, and

transmission means operatively coupling said prime mover means to drive said rotary brush means.

l =l l =l =l= 

1. A machine for cleaning a surface comprising: a frame supported by wheels and having a forward end and a rearward end, said wheels including a pair of spaced drive wheels interconnected by a rigid axle, said axle mounted for rotation in said frame, said wheels mounted for rotation on said axle, differential drive means associated with said axle and each of said drive wheels, said differential drive means being adapted to drive each said drive wheel in a first direction responsive to rotation of said axle in said first direction and being adapted to allow said axle to rotate in said wheel when said axle is rotated in the opposite direction from said first direction, a self-contained prime mover mounted on said frame, a first rotary brush means having a first sub-frame mounted on the forward end of said frame, said first brush means being adapted to contact said surface, a second rotary brush means having a second sub-frame located adjacent to the forward end of said frame and adjacent to said first brush means, said second brush means being adapted to contact said surface, means mounting said second sub-frame on said first sub-frame for movement between a first position located sidewardly of said first brush means and a second position located substantially forwardly of said first brush means, whereby as said machine travels forwardly said first brush means contacts said surface along a path substantially the same as said second brush means when said second brush means is in said second position, and transmission means operatively coupling said prime mover to drive said first and second rotary brush means and operatively coupling said primE mover to drive said axle.
 2. A machine for cleaning a surface comprising: a frame having a forward end and rearward end, said frame being supported by wheels including drive wheel means for moving said machine along said surface, a self-contained prime mover mounted on said frame, a first sub-frame mounted on the forward end of said frame, and a first rotary brush mounted for rotation on said first sub-frame and adapted to contact said surface, a second sub-frame located adjacent to the forward end of said frame and adjacent to said first sub-frame, a second rotary brush mounted for rotation on said second sub-frame and adapted to contact said surface, and means mounting said second sub-frame for swinging movement from a location sidewardly of said first sub-frame to a location forwardly of said first sub-frame, power transmission means operatively connecting said prime mover to drive said first and second rotary brushes and to drive said drive wheel means, said transmission means including a hydraulic pump having an outlet and an inlet, said hydraulic pump being driven by said prime mover, first and second hydraulic motors operatively connected to drive said first and second brushes, respectively, and a third hydraulic motor operatively connected to drive said drive wheel means, said first, second and third hydraulic motors each having an inlet and an outlet, said inlets being operatively coupled to the outlet of said hydraulic pump to receive hydraulic fluid therefrom, said first hydraulic motor mounted on said first sub-frame and having a drive shaft, said drive shaft being drivably connected to said first rotary brush, said second hydraulic motor mounted on said second sub-frame and having a drive shaft, said drive shaft being drivably connected to said second rotary brush, and a hydraulic piston and cylinder, and means operatively connecting one of the piston and cylinder to said second sub-frame and means affixing the other of said piston and cylinder to said first sub-frame, said hydraulic piston and cylinder being operatively coupled to the outlet of said hydraulic pump to swing said second sub-frame about its mounting to said first sub-frame.
 3. The machine of claim 2 wherein said transmission means includes a hydraulic fluid system comprising: a hydraulic fluid sump, first conduit means in fluid communication with said sump and the inlet to said hydraulic pump, second conduit means placing said first and second hydraulic motors in serial fluid communication with the outlet of said hydraulic pump, a first check valve means, and third conduit means in fluid communication between said first check valve means and the outlet of said second hydraulic motor, said first check valve means operative to allow flow away from said first and second hydraulic motors, fourth conduit means in fluid communication between said third conduit means and the inlet to said third hydraulic motor, fifth conduit means in fluid communication between the outlet of said third hydraulic motor and said sump, sixth conduit means is fluid communication between said fourth conduit means and said sump, and a first four-way valve means operatively interposed in said second and sixth conduit means.
 4. The machine of claim 3 wherein said hydraulic fluid system further comprises; second check valve means interposed in said sixth conduit means between said first four-way valve means and said fourth conduit means, said second check valve means operative to allow flow in a direction from said first four-way valve means to said fourth conduit means, seventh conduit means in fluid communication with said sump, and variable flow valve means interposed in said fourth conduit means and operatively coupled to said seventh conduit means to proportion hydraulic fluid flow between said fourth conduit means and said seventh conduit means.
 5. The machine of claim 4 wherein said hydraulic fluid system further comprises: a second four-way valve means operatively interposed in said fourth and fifth conduit means, said second four-way valve means located in said fourth conduit means between said variable flow valve means and said third hydraulic motor.
 6. The machine of claim 5 wherein said hydraulic cylinder has inlets for supplying fluid thereto for reciprocatively actuating said piston, said hydraulic fluid system further comprising: eighth conduit means in operative fluid communication between said second conduit means and a first inlet of said hydraulic cylinder, ninth conduit means in operative fluid communication between a second inlet of said hydraulic cylinder and said sump, and third four-way valve means operatively interposed in said eighth and ninth conduit means.
 7. The machine of claim 5 wherein said hydraulic fluid system further comprises: tenth conduit means in fluid communication between said sump and said fifth conduit means at a location between said third hydraulic motor and said second four-way valve means, and third check valve means operatively interposed in said tenth conduit means and being operative to allow fluid flow in a direction from said sump to said third hydraulic motor.
 8. A machine for contacting a surface with a rotary fluid working tool comprising: a frame supported by wheels and having a forward end and a rearward end, a prime mover mounted on said frame, a first rotary tool means including a first sub-frame mounted on the forward end of said frame, and including a first tool rotatably mounted on said first sub-frame, said first tool means being so constructed to contact said surface with said first tool, a second rotary tool means located adjacent to the forward end of said frame and adjacent to said first tool means, said second tool means including a second sub-frame and including a second rotary tool rotatably mounted on said second sub-frame, said second tool means being so constructed to contact said surface with said second tool, mounting means mounting said second sub-frame on said first sub-frame for movement in a vertical direction relative to said first sub-frame when said first and second tools are in contact with said surface, and power transmission means operatively coupling said prime mover to drive said first and second rotary tool means.
 9. A machine for contacting a surface with a rotary fluid working tool comprising: a frame supported by wheels and having a forward end and a rearward end, a prime mover mounted on said frame, a first rotary tool means including a first sub-frame mounted on the forward end of said frame, and including a first tool rotatably mounted on said first sub-frame, said first tool means being so constructed to contact said surface with said first tool, a second rotary tool means located adjacent to the forward end of said frame and adjacent to said first tool means, said second tool means including a second sub-frame and including a second rotary tool rotatably mounted on said second sub-frame, said second tool means being so constructed to contact said surface with said second tool, mounting means mounting said second sub-frame on said first sub-frame for movement between a first position located sidewardly of said first tool means and a second position located substantially forwardly of said first tool means, said second tool means in said second position being located so that, as said machine travels in a forward direction, said first tool contacts said surface along substantially the same path as said second tool contacts said surface, power means connected between said first sub-frame and said second sub-frame for moving said second tool means between said first and second positions, and power transmission means operatively coupling said prime mover to drive said first and second rotary tool means.
 10. The machine of claim 9 wherein said power means comprises: a hydraulic piston and cylinder including mEans operatively connecting one of the piston and cylinder to said second sub-frame and means connecting the other of said piston and cylinder to said first sub-frame, said machine further comprising: hydraulic pump means driven by said prime mover for selectively supplying hydraulic fluid to said piston and cylinder means.
 11. A machine for contacting a surface with a rotary fluid working tool comprising: a frame supported by wheels and having a forward end and a rearward end, a prime mover mounted on said frame, a first rotary tool means including a first sub-frame mounted on the forward end of said frame, and including a first tool rotatably mounted on said first sub-frame, said first tool means being so constructed to contact said surface with said first tool, a second rotary tool means located adjacent to the forward end of said frame and adjacent to said first tool means, said second tool means including a second sub-frame and including a second rotary tool rotatably mounted in said second sub-frame, said second tool means being so constructed to contact said surface with said second tool, mounting means detachably mounting said second sub-frame to said first sub-frame for movement between a first position located sidewardly of said first tool means and a second position located substantially forwardly of said first tool means, and power transmission means operably coupling said prime mover to drive said first and second rotary tool means.
 12. A machine for cleaning a surface comprising: a frame supported by wheels and having a forward end and a rearward end, a self-contained prime mover mounted on said frame, a first rotary brush means having a first sub-frame mounted on the forward end of said frame, said first brush means adapted to contact said surface, a second rotary brush means having a second sub-frame and being adapted to contact said surface, said second brush means being located adjacent to the forward end of said frame and adjacent to said first brush means, means mounting said second sub-frame on said first sub-frame for swinging movement between a first position located sidewardly of said first brush means and a second position located substantially forwardly of said first brush means, first wiper blade means mounted adjacent the rearward end of said frame to direct fluid to a means for removing said fluid from said surface, second wiper blade means mounted on and rearwardly of said second brush means, said second wiper blade means adapted to direct fluid present on said floor rearwardly and sidewardly to be picked up by said first wiper blade means as said machine traverses a forward path, and transmission means operatively coupling said prime mover means to drive said rotary brush means. 